The blendshapes method is a technique for the creation of realistic and semi-realistic three-dimensional (3D) animation. The blendshapes method can deform a neutral shape (for example, an expressionless face) of a virtual entity to a target shape (for example, laugh, frown, pursed lips, closed eyelids, and so forth). Typically, each target shape deforms only a part of the virtual entity. Blendshapes associated with different parts of the virtual entity can be mixed and matched to form a number of poses. For example, a frown can be mixed with a smile to form an apologetic expression. A blendshape with pursed lips can be mixed with frowning eyes to form an expression of determination or a look of disapproval.
To provide a high quality of animation, the blendshapes method often requires a large number of target shapes to represent poses in detail. Due to this large number of the target shapes, it is difficult to achieve real-time performance using the blendshape method.